Brain scans may predict jurors' decisions

Jury duty typically involves filling out forms, waiting at the courthouse and answering questions from attorneys. Might it one day also include a brain scan? Recent research conducted by scientists from Caltech and Japan suggests it's a possibility.

The researchers found through MRI scans that sympathy for a defendant and leniency during sentencing strongly correlates to heightened activity in a tiny region of jurors' brains.

The research was based on occurrences in Japan.

Japan was essentially without a jury system between 1943 and 2004. Once re-established, jury trials in Japan were set up a bit differently than in the United States. In Japan, the jury determines both if someone is guilty of a crime and how long they will be sentenced to prison. In the U.S., juries are only involved in sentencing if a death sentence is to be handed out.

Colin Camerer, the Robert Kirby professor of behavioral finance and economics at Caltech, said the Japanese system requires jurors to do two contradictory things. During the phase of the trial when jurors are determining whether someone is guilty, they are expected to leave their emotions at the door and look at the cold, hard facts.

But during the sentencing phase, they are expected to weigh the factors that led the defendant to commit the crime, essentially putting themselves in that person's shoes and feeling what they felt.

Because many Japanese have had little-to-no experience with serving on a jury, the scientists wanted to see if the average citizen was up to the task.

"Can Japanese brains make good jury decisions?" asked Camerer.

Researchers presented test subjects with two types of trials, Camerer said. The first featured a highly sympathetic defendant - a husband who killed his wife to end the suffering caused by her cancer, for example.

The second type featured an unsympathetic defendant, such as a man who killed his ex-wife out of revenge.

The faux jurors were then loaded into an MRI machine and asked to sentence the defendants while scientists peered into their brains.

What they found was the jurors who were most likely to provide a short sentence for the sympathetic killer and a long sentence for the unsympathetic killer showed heightened activity in the insula, a small piece of the brain involved in feeling emotional and physical pain.

Camerer calls the insula the "ambassador to the brain, particular with discomfort."

The insula not only allows the brain to process a person's own emotions and discomfort, it helps them understand the feelings of others, Camerer said.

"When somebody says `I feel your pain,' it's a literal brain interpretation of what it means," he said. "The definition of sympathy is feeling what someone else feels."

Camerer said the research indicates that despite Japan's short history of having jury trials, jurors are perfectly capable of providing punishments that fit the crime.

But he also said it raises the question of whether jurors who are naturally wired to strongly feel sympathy are capable of ignoring their emotions while trying to make an objective decision about guilt or innocence.

"The hardest things by far are where you have a celebrity defendant, rape cases, racially charged cases," Camerer said. "We should be able to say this juror is going to be good at it and this juror is going to be bad at it. Those are things we might be able to measure."

Prosecutors and defense attorneys already ask questions of potential jurors to narrow down the pool to only the most capable individuals - at least in theory - but Camerer wondered if that system is enough.

"We should ask the brain instead of asking the person," Camerer said.

Neal Curatola, an Anaheim-based defense attorney, said the idea of looking at brain activity when selecting a jury might take the justice system into "scary area."

He worried that prosecutors might use such scans to eliminate "otherwise competent jurors."

"Picking a jury isn't an exact art. It isn't a science. It was never intended to be," Curatola said. "Maybe I'm old school."

El Monte Mayor Andre Quintero, a prosecutor in the Los Angeles City Attorney's Office, called the concept "Orwellian," but was a bit more receptive to it.

"The application of science in selecting a fair and impartial juror provides a whole new opportunity for a conversation," Quintero said. "It's an interesting conversation for the criminal justice system to have."

But Camerer said the legal system is "skeptical" of such innovations, so brain scans aren't likely to become a legal tool any time soon.